CNC Lathe Research Articles

Analisis Kekasaran Mesin Bubut Konvensional dan CNC TU-2A Dengan Rpm 1500 Menggunakan Poros Aluminium

Conventional and CNC lathes are one of the numerical components as a production machine for manufacturing purposes that the industry relies on. To get the level of smoothness of a surface plays a very important role in the planning of a machine component, especially concerning the problem of friction, wear, resistance to fatigue as well as for surface roughness is closely related to the function of the component The manufacture of components does not merely have to have a small or smooth roughness value, but must also be in accordance with the functions and requests of the designer. TU 2A CNC lathe has a smaller roughness value (smoother) than the turning results using a conventional lathe. This is evidenced from the results of roughness testing where the smallest roughness value of the TU 2A CNC lathe is 1.27 µm and the smallest roughness value of the conventional lathe is 1.38 µm while the largest roughness value of the TU 2A CNC lathe is 2.68 µm and the surface roughness value for conventional lathes is 2.71 µm. The surface roughness class of the results of this study is in N6 to N8

Dynamic reliability analysis of CNC lathe spindle-bearing system with thermal effect in radial runout

As one of the key components of computerized numerical control (CNC) lathes, the dynamic characteristics of spindle-bearing system has a vital influence on machining performance. Analyzing the kinematic error of spindle-bearing system is of great significance for investigating its radial runout and optimizing CNC lathe. The failure mode of CNC lathe spindle-bearing system with thermal effect is defined as the dynamic displacement of shaft end exceeds the allowable radial runout. Firstly, a dynamic model of system with thermal effect under random geometric parameters is presented to carry out the reliability analysis of radial runout. The stochastic perturbation method is applied to determine the first four moments of system dynamic displacement. Random variables and derivatives of system differential equations can be arranged into two-dimensional matrices used with Kronecker algebra. In addition, the reliability and its reliability sensitivity of system are obtained to study the influence of random parameters on the reliability of system. A CJK-6130 CNC lathe is used as a practical example of proposed model. Furthermore, the comparison between numerical calculation and Monte Carlo simulation is used to verify the proposed method. Eventually, the effects of mean values and variances of bearing random parameters on the radial runout are discussed.

Research and prospects of CNC lathe

Research and prospects of CNC lathe

Roboto su tiesiaeigio judėjimo/pozicionavimo įrenginiu automatinės sistemos efektyvumo tyrimas

The work presents an assessment of the efficiency and operational costs of modernized manufacturing process. The process consists of turning operations on two CNC lathe machines. Two options for modernization are proposed: installation of 2 robots automated system and installation of an automated system of one robot on a linear motion track for positioning. The purpose of the study is to prove the advantage of option with one robot on a linear motion track device. The process modelling is performed in Visual Components software. ABB 6-axis robot IRB 4600 and the linear motion track device ABB IRBT 4004 of the same manufacturer were chosen for the research. Keywords: robot, linear motion track, Visual Components software.

Evaluation of the machinability performance of PH 13-8 Mo maraging steel used in the aerospace industry

This study focused on investigating the impacts of machining parameters on cutting force (Fc), surface roughness (Ra), cutting power (Pc), and specific cutting energy (SCE) and determining optimum machining parameters in turning PH 13-8 Mo stainless steel. For this purpose, an experimental design was set with Taguchi's L32 orthogonal array by identifying cutting parameters such as cutting speed (Vc), feed rate (f), and depth of cut (ap) at different levels. The turning tests were carried out on the CNC lathe using a coated carbide cutting tool under dry-cutting conditions. Signal/Noise (S/N) ratio and analysis of variance (ANOVA) were used to determine the impacts of cutting parameters on Fc, Ra, Pc, and SCE values obtained after turning experiments. In addition, regression analysis was performed to identify the correlation between Fc, Ra, Pc, and SCE and cutting parameters through linear and quadratic regression models. The main findings of the study are that the lowest Fc (A1B1C3), Ra (A1B1C4), Pc (A1B1C1) and SCE (A2B4C3) values were measured at 287.8 N, 0.59 µm, 697.16 W and 1549.55 J/mm3 in turning PH 13-8 Mo martensitic stainless steel. ANOVA, the most important process parameter affecting Fc, Ra, Pc, and SCE was feed rate at the rate of 85.57%, 84.93%, 71.10% and 60%. It was observed that the mathematical model findings obtained with the test results are in good agreement. In general, wear mechanisms such as adhesion, BUE, chips, crater, notch, fracture, and chipping on the cutting tool were detected in the turning of PH 13-8 Mo stainless steel.

The optimization method of CNC lathe performance based on Morris sensitivity analysis and improved GA algorithm

This study achieved the goal of guiding bed design and optimization by conducting multi-objective optimization research on the performance of CNC lathe beds. In this study, Morris analysis was first performed on the sensitivity of the parameters, and then out to optimize the parameters using a combination of neural network and genetic algorithm. The loss function value, RMSE error accumulation, recall, sensitivity and specificity of the ASSGA-BP optimization model were better. The maximum error between the predicted and true values of the ASSGA-BP model was 0.28 mm. In the performance study of the multi-objective optimization method based on the Morris sensitivity analysis and the improved GA algorithm, the average MAE value is 0.91 %. The average RMSE value is 0.59 %. Also, the new model is significantly better than the NSGA-II, EGA, and FGA algorithms in terms of both the number of final non-dominated solutions and the speed of reaching convergence. The above results demonstrate that the model proposed in this study has high performance, can achieve faster convergence and has the best stability of the convergence state. The innovation of this article lies in the use of the Morris method to screen and evaluate numerous parameters in order to improve the accuracy of the calculation results and ensure the effectiveness of the optimization results. The improved algorithm overcomes the problems of BP neural network and can effectively improve the generalization performance of the neural network, thereby improving the prediction accuracy of the model.

СИНТЕЗ СЛЕДЯЩЕЙ СИСТЕМЫ УПРАВЛЕНИЯ ЭЛЕКТРОПРИВОДАМИ ПОДАЧИ И ГЛАВНОГО ДВИЖЕНИЯ ТОКАРНОГО СТАНКА С ЧИСЛОВЫМ ПРОГРАММНЫМ УПРАВЛЕНИЕМ

Relevance Modern requirements for turning accuracy of parts during turning are constantly increasing. In order to provide them, in addition to using modern CNC machines and tooling, it is necessary to minimize errors arising during the operation of the machine drives (main and feed drives), as well as the cutting tool that is used during the process. This task can be carried out using specialized tracking systems for controlling the electric drive of a CNC lathe. The use of the control system allows you to control nondeterministic cutting parameters and ultimately provide the required amount of roughness. Aim of research The main aims of the research develop a model of the tracking system for controlling the feed and main motion of the CNC lathe. Research methods The control system model is synthesized using the MATLAB SIMULINK program. Results As part of the study, the MATLAB SIMULINK software package was used to develop a model of the tracking system for controlling the feed motors and the main motion of the CNC lathe. As a result of the operation of the servo control system, it has become possible to determine the values of non-deterministic cutting parameters, which will ensure the accuracy of processing the surfaces of the workpiece with a minimum error value.

THE EFFECT OF ATOMIZED SOYBEAN OIL EMULSIONS USED AS CUTTING FLUID ON THE CUTTING PERFORMANCE

Within the scope of sustainable production, a natural liquid mixture that will act as cutting fluid is sprayed with a different system. The liquid consisting of water and soybean oil was pulverized by ultrasonic atomization method and used by spraying with 4 bar compressed air. In this study, it was aimed to investigate the effects of AISI 4140 steel on machinability in CNC lathe by using uncoated carbide insert (SECO WNMG080404-M1). Three cutting speeds (150, 200, 250 m / min), three feed rates (0.1, 0.15, 0.2 mm / rev) with four cutting fluids (1%, 5%, 10% soy oil-water mixture and commercial cutting fluid) and the comparison was made by making experiments under dry cutting conditions. In all experiments, the cutting depth was 1 mm and the cutting length was 100 mm. As a result of the experiments, cutting force, surface roughness and tool wear values were examined and contact angle measurements of cutting fluids were made. The best results in all parameters were achieved by spraying a 10% soybean oil-water mixture using an ultrasonic atomizer. The best results in all parameters were achieved by spraying a 10% soybean oil-water mixture using an ultrasonic atomizer. The worst values occurred in experiments conducted under dry cutting condition. In addition, SEM photographs were taken to observe the type of tool wear. The obtained values were analyzed with the ANOVA method and the results were evaluated with 3D surface graphics. After evaluating the analysis results, percentage impact rates, regression analysis equations and optimization values are proposed.

Curriculum reform and innovation for CNC lathe and milling processing certificate under the "1+X" certification system

With the development of smart manufacturing, CNC lathe and milling processing technology play an increasingly vital role in modern manufacturing. The "1+X" certification system offers a new pathway for vocational education to cultivate highly skilled professionals. This paper focuses on the curriculum system of the CNC lathe and milling processing certificate and explores strategies for curriculum reform and innovation under the guidance of the "1+X" certification system. By examining the existing curriculum system and analyzing the discrepancies between industry demands and the current teaching situation, specific reform measures are proposed. Additionally, in line with the concept of industry-education integration, innovative approaches to curriculum content and teaching methods are explored, as well as ways to leverage information technology for improving teaching efficiency and quality. The research shows that by optimizing curriculum structure, updating teaching content, improving teaching methods, and enhancing practical components, it is possible to significantly enhance students' skills and innovation capabilities, better meeting the needs of enterprises in the context of Industry 4.0.

A fuzzy ANP-based criticality analyses approach of reliability-centered maintenance for CNC lathe machine components

Calculation of the criticality score and its analysis are important for the reliability-centered maintenance (RCM) of CNC lathe machine components. The tools of a CNC lathe machine include complex critical part and sub-systems. The reliability of parts decline due to the independent system fault. To identify the essential components of CNC lathe machine tools, a system level component criticality analysis method is proposed. In this study, a comprehensive framework of criticality-based RCM implementation through experimentation of a CNC-lathe machine is proposed. The criticality of machine components were identified by investigating their dependency on the criteria and sub-criteria. Five main criteria were found effective for the criticality of the components which are the cost, complexity, sustainability, functional dependency, and safety impacts. Fuzzy analytical network process (FANP) approach was employed to evaluate criticality scores for eleven-component of a CNC lathe machine. This is a preliminary study and aims to contribute to the literature and practitioners in many ways. The primary focus of our method lies in its capability to predict criticality values for a manufacturing system in absence of historical maintenance data relying on the expertise/intuition of the operator(s) for decision making for the predictive maintenance of the system with the help of fuzzy ANP approach. It was found that the turret was the most critical component with a metric of 0.0641 which was also found to be over 3 times more critical than the least critical hydraulic system, which had a criticality metric of 0.0187. This novel FANP framework provides a credible solution to real-world RCM scheduling and can be applied to any manufacturing system-related application.

Robust modeling for thermal error of spindle of slant bed lathe based on error decomposition

Thermal error of spindle is critical to the slant bed CNC lathe towards high machining precision. The heat generated by the spindle itself contributes to the thermal error indeed. However, the thermal error is also influenced by the thermal deformation of other components such as the turret and lathe bed, especially in complex structured slant-bed CNC lathes where error coupling commonly exists. In order to achieve robust modeling of thermal error, a decomposition method was proposed in this paper to separate the contributions of spindle, turret and lathe bed from the overall measured thermal deformation. The thermal error coupling relationship was established from the perspective of machine tool construction. A specific testing scheme was designed to determine the parameters of decoupling model. Additionally, a comparative experiment was carried out by placing the sensor support horizontally and vertically to verify the effectiveness of thermal error decoupling. Taking T65-750 high-precision CNC lathe as the object, the relationship between thermal error and tilt angle in the X-direction of the headstock, bed, and other components was revealed, achieving robust prediction of thermal error irrespective of the ambient temperature subject to change. Finally, the thermal error model built based on error decomposition was applied to improve the machining accuracy of cylindrical parts dramatically in practice.

Identification of maintenance significant items for machine tools by integrating DEMATEL and MABAC with spherical fuzzy sets

The identification of maintenance significant items (MSIs), which is a multi-criteria decision-making (MCDM) process, is the primary phase of reliability centered maintenance. The identification process is typically vague and uncertain as a result of the structural complexity and functional diversity of machine tools. Therefore, there are limited effective methods for identifying MSIs in machine tools. In this study, we propose a novel MSI identification method that integrates two MCDM methods, namely the decision-making trial and evaluation laboratory (DEMATEL) and multi-attributive border approximation area comparison (MABAC). A novel extension of the fuzzy theory called the spherical fuzzy (SF) set concept is combined with the integrated DEMATEL-MABAC method. SF-DEMATEL is used to evaluate the criteria weights of machine tools. Then, based on the judgement information regarding alternatives under each criterion, SF-MABAC is used to identify and rank MSIs. The proposed integration method was applied to a CNC lathe with six criteria and 11 alternatives. Robustness analysis was conducted to verify the stability and effectiveness of the proposed method. The results demonstrate that the integration of DEMATEL and MABAC under the SF concept is a reasonable and applicable method for MSI identification. The results support engineers into reasonably identifying the significant maintenance items for machine tools.

Steady state prediction model and spectrum characteristics analysis of cutting force for CNC lathe considering variable machining parameters

This paper presents a steady state cutting force prediction model for CNC lathe considering feed displacement. The frequency spectrum characteristics of the cutting force in principal direction are analyzed. The turning test for 12Cr18Ni9 stainless steel workpiece is carried out by CNC machine tool ETC1625P firstly, and the real-time displacement data of worktable in the turning process are obtained. The cutting force data varying with the displacement of the worktable under different cutting parameters are obtained by cubic spline interpolation. The mechanical force model including metal shearing force and plowing force is established, so as to predict the steady state cutting force accurately corresponding to different displacement of the worktable. The influence of different cutting parameters on the amplitude frequency characteristics for the low frequency part of the cutting force in principal direction is studied by using wavelet packet decomposition and fast Fourier transform. The results show that the method can predict the steady cutting force accurately and reflect the amplitude frequency characteristics of the low frequency part for the cutting force in principal direction under different cutting parameters.

Modeling and Optimization of Surface Integrity and Sliding Wear Resistance of Diamond-Burnished Holes in Austenitic Stainless Steel Cylinder Lines

This article outlines a technology for hole-finishing in short-length cylinder lines to improve wear resistance. The technology is based on an optimized diamond-burnishing (DB) process. The latter was implemented on conventional and CNC lathes, milling machines, and machining centers using a simple burnishing device with an elastic beam. The material used in this study was AISI 321 austenitic stainless steel. The governing factors used were the radius of the diamond insert, burnishing force and feed rate. The objective functions relating to surface integrity characteristics were selected on the basis of their functional importance relative to the wear resistance of the processed hole surface: height and shape roughness parameters, surface microhardness, and surface residual axial and hoop stresses. The one-factor-at-a-time method (used to reduce the factor space), a planned experiment, and regression analyses were used. The multi-objective optimization tasks, which were defined for three diamond insert radius values of 2, 3, and 4 mm, were solved via the Pareto-optimal solutions approach available for a non-dominated sorting genetic algorithm (NSGA-II). Using the optimal values of the governing factors selected from the Pareto fronts, cylinder lines were processed. Samples were then cut from these cylinder lines for reciprocating sliding wear tests under two modes: dry friction and boundary lubrication friction. Additionally, wear test samples were cut from the cylinder line, which was finished with traditional grinding. A finite element simulation was then used to select an appropriate pressing force. The results obtained from the reciprocating sliding wear tests under both the dry and boundary lubrication friction regimes show that to minimize the wear on cylinder lines made of AISI 321 steel, DB with a diamond insert of radius 2 mm is the optimal finishing process.

Analisis Pengaruh Variasi Kecepatan Spindel Dan Feeding Terhadap Nilai Kekasaran Permukaan Proses Finishing Bubut CNC

In the industrial sector, technological progress has experienced very rapid development. So that the manufacturing industry is required to be able to produce quality products and a high level of accuracy with fast processing. One machine that can meet these demands is a CNC lathe, where a CNC lathe is a machine that is controlled using a computer system in its operation. In the machining process of CNC lathes, the level of surface roughness of the machining material is of great concern, because the lower the surface roughness value, the better the quality of the product. Therefore, the aim of this study was to obtain a low surface roughness value using a finishing cutting edge. The material used is AISI 1045 steel which is turned using a MORI SEIKI SL-25 CNC machine. The parameters used are spindle speed and feeding. The research method used was the Taguchi method with an orthogonal matrix L9(32) experimental design and 3 replications were carried out to reduce large deviations. The result of this research is to obtain a combination of parameters that produce minimum surface roughness values, namely spindle speed of 1804 rpm and feeding of 0.1 mm/put. And the parameter that has the greatest effect on the value of roughness is feeding with a difference of 16.029 and the one that has the least effect on the value of surface roughness is spindle speed with a difference of 1.384.

Experimental study of geometric error of CNC turning machine tools based on ISO 13041-6

The product quality of machining results is greatly influenced by the accuracy and precision of CNC lathe machine tools. Regular inspection of the geometric inaccuracy of the machine tool is necessary to verify its operational viability. This research contribution focuses on conducting experimental studies to evaluate machine tool geometric error. The aim is to explore cost-effective measurement methods as alternatives to direct measurements, which often involve laser interferometers and ball bar tests. The objective of this study is to investigate the geometric inaccuracy of a CNC turning machine by conducting experimental cutting tests in accordance with ISO 13041-6:2009. The testing will utilize conventional workpiece forms and requirements, including circularity features, flatness, circular features, and maybe combination features. Several geometric errors that can be acquired with this method include circularity errors, linear positional errors, and squareness errors. The cutting test for each workpiece feature of the given shape and specification requires the use of 5 specimens. Consequently, the mean value of the geometric error may be computed. The geometric error value is derived by the analysis of measurement data collected from a Coordinate Measuring Machine (CMM) applied to a specimen of the machined workpiece. Moreover, the evaluation of the geometric error condition of machine tools is ascertained through the comparison of the average data for each category of geometric error against the permissible standard values given in ISO 10791-2, ISO 10791-4, and ISO 13041-4. The findings of the study indicate that the implementation of the object machine study is not viable for the production of machined workpieces of satisfactory quality. This is primarily due to the presence of geometric errors in CNC turning that exceed the acceptable tolerance levels. Specifically, these errors manifest as linear positional deviations along multiple coordinates along the X-axis and Z-axis, as well as squareness deviations between the X-axis and Z-axis. The maximum value of the linear positional error along the X-axis is 55.2 μm, while the maximum value of the linear positional error along the Z-axis is 25.6 μm. Additionally, the greatest observed squareness error is 37.3 μm. The X and Z machine axes exhibit deviations beyond acceptable limits in terms of unidirectional accuracy and unidirectional repeatability, as per the established norm

A thermal error modeling method for CNC lathes based on thermal distortion decoupling and nonlinear programming

A thermal error modeling method for CNC lathes based on thermal distortion decoupling and nonlinear programming

Risk Identification Model for Lean Manufacturing Improvement

Small- and medium-sized manufacturing enterprises (SMEs) were confronted with a variety of difficulties due to the increasingly complex market environment, and many of them could not make enough profits to proceed with their manufacturing tasks. The objective of this study was to develop a model of risk management by integrating several risk tools at manufacturing companies. This study was also intended to improve the decision making by providing quantitative analysis at each step of risk management and improve lean practices. Risk quantitative analysis methods such as failure modes and effects analysis (FMEA) and multi-objective optimization on the basis of ratio analysis (MOORA) were applied in this study to identify the potential risks. Moreover, the risk assessment was used to categorize risks into different severity levels. The manufacturing data obtained from a case study was utilised to calculate the risk priority number (RPN). The risk mitigation actions were formulated to reduce the original RPN and the final RPN value decreased to a normal standard in the end. Overall, this study optimised the risk management of one case study SME and improved lean manufacturing practices. By establishing the risk identification model and applying common lean manufacturing concepts in reducing wastes at actual manufacturing processes, the manufacturing enterprise could manage to optimize the operations and increase the actual manufacturing productivity. The machining and assembly processes of diesel engines were optimized and improved with the decrease of RPN and the selection of the CK6150 CNC lathe that owns the highest MOORA assessment value.

Исследование отклонений формы изделий из быстрорежущей стали при точении фрезерованием на станках с ЧПУ

Investigation of form deviations of cylindrical high-speed steel (HSS) products made under turning-milling operation by CNC-controlled lathe machining center (further CNC) with auxiliary drive axle is given. Technological support of high-speed steel products quality made by turning milling operation on a CNC lathe machining center with an auxiliary drive axle takes effect owing to the shape deviation reduction. Planning of experiments was carried out according to the Taguchi method for four factors and three levels. The experiment was conducted on a DMG NEF 400 lathe machining center having an auxiliary drive axle, which allows machining modes to be performed with a rotating tool. Samples of high-speed steel R6M5K5-MP were used. Machining operation was made according to the scheme of orthogonal turning by milling. A core carbide mill CCM 4321 was used as a cutting tool. Out-of-roundness (lobing) was estimated using optical method. All measurements were carried out on the Bruker Contour GT-K1 optical profilometer. Surface micro-dimensions were measured by optical scanning of the surface. Surface optical scanning resulted in a point cloud was obtained that mirrors micro-dimensions of the cylindrical profile of the piece partmeasured section. The obtained data obtained made it possible to measure a lobing that occurs under orthogonal milling turning method. The influence of cutting modes on the shape and size of the maximum peaks of the cut is proved. The smallest facet pattern value is observed for milling width a_e in the range of 3,5...5,5 mm with high feed values for the tooth f_z and low cutting speed v_c. The largest cut height is observed at the average values of a_e, a_p, v_c. It is an optical profilometer that is an effective means of measuring facet patterns or lobings. The results obtained in the work allow predicting form deviations of a blank made of high-speed steel under turning milling operations on CNC machines. The results of the study can be used to improve rotary cutting tools quality in the tool industry.

Determination of the Predictive Labor Intensity of Manufacturing Parts on CNC Lathes Using the Feature Recognition

The problem of labor intensity operational forecasting of manufacturing parts on CNC lathes is considered. As a method, the recognition of structural and technological elements (features) of a part according to its 2D model was chosen to calculate the predictive labor intensity of machining. The processing of parts of the “sleeve” type on CNC lathes is considered. The feature recognition process is implemented in the form of an applied CAD/CAM system, which is fed with an electronic 2D model and a table of parameters of the manufactured surfaces. These parameters include accuracy and surface roughness requirements, the type of thread being cut, its pitch, the coordinates of the start and end points of the thread. At the output, a running program (NC) is formed for a CNC machine, designed in the form of standard cycles. Automatic assembly of NC becomes possible due to the use of technological templates for processing typical structural elements specially developed for this purpose. Technological templates are developed for all features typical for turning operation (end, open zone, semi-open zone, closed zone, and thread). For external and internal surfaces of the part technological templates are different, because various tools and strategies for constructing trajectories are used to process them. Formalization of closed area processing is of particular difficulty. Therefore various types of closed zones (undercut, groove, groove for thread exit, and face undercut) are classified at the stage of recognition. A separate technological template for their processing has been created for each type of closed areas. To determine the complexity, a standard simulation module NC is used. The results of model adaptation to current production are obtained.